Lindell Audio 500 Series User manual

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of this document may be reproduced in any form without explicit written consent from Lindell Audio. Lindell Audio is
a RAD Global Distribution company.
PeQ-501a
500-Series Equalizer
Specications
Power Requirements +/- 16V
Input Impedance 2.4 kΩ, op-amp balanced
Output Load Impedance 70 Ω transformer-balanced
Frequency Response +/- 1dB 20 Hz to 20 kHz
Dimensions Width:76 mm (3”)
Height: 178 mm (5.25”)
Depth: 229 mm (9”)
Weight 1.47 kg (3.25 lbs)

1. Read these instructions.
2. Keep these instructions
3. Heed all warnings.
4. Follow all instructions.
5. Do not use this apparatus near water.
6. Clean only with dry cloth.
7. Install in accordance with the manufacturer’s
instructions.
8. Do not install near any heat sources such
as radiators, heat registers, stoves, or other
apparatus that produce heat.
9. Protect the power cord from being walked on
or pinched particularly at plugs, convenience
receptacles, and the point where they
exit from the apparatus. If the power cord
becomes frayed, stop using immediately.
10. Use only attachments/accessories specied
by the manufacturer
11. Use only with a cart, stand, tripod, bracket
or table specied by the manufacturer, or
sold with the apparatus. When a cart is used,
use caution when moving the cart/apparatus
combination to avoid injury from tip-over.
12. Unplug this apparatus during lightning storms
or when unused for long periods of time.
13. Refer all servicing to qualied service
personnel. Servicing is required when
the apparatus has been damaged in any
way, such as power supply cord or plug is
damaged, liquid has been spilled or objects
have fallen into the apparatus, the apparatus
has been exposed to rain or moisture, does
not operate normally, or has been dropped.
14. This apparatus shall not be exposed to
dripping or splashing, and no object lled with
liquids, such as vases, shall be placed on the
apparatus.
15. Note that this apparatus is not completely
disconnected from the AC mains service when
the power switch is in the OFF position.
16. The mains plug or power inlet on the product
is used as the disconnect device, so the
disconnected device shall remain readily
operable when reconnected.
17. Any changes or modications not expressly
approved in this manual could void your
authority to operate this apparatus.
Important !
Be sure to only use the power connection
intended for your 500-series rack.
The triangular lightning ash icon is in-
tended to alert the user to the presence
of uninsulated, dangerous voltage within
Installation
1. Power off the 500-series rack
that the PeQ-501a is to be in-
stalled in.
2. Make sure nothing surrounds
the card edge connector on the
back of the PeQ-501a.
3. Carefully slide the PeQ-501a
into an empty slot in your
500-series rack
4. Ensure that the PeQ-501a edge
connector is installed secure-
ly into the connector on the
500-series rack
5. Install screws on the PeQ-501a
faceplate to secure the unit.
INITIAL SETUP:
Using balanced XLR cables, con-
nect the PeQ-501a’s inputs and outputs from your 500-series chassis
to your mixing bus or patch bay. Set the EQ button to the on position,
and apply power.
Basic Use
On the PeQ-501a, low-frequency options are present-
ed on the left of the control panel; high-frequency op-
tions are on the right.
Low-Frequency Controls (left)
1. CPS: (Cycles per second) Sets the operating fre-
quency of the unit’s low-frequency Boost and At-
ten controls.
2. Atten: Sets the amount of low shelf cut to be ap-
plied to the frequency set by the CPS switch.
3. Boost: Sets the amount of boost applied to the fre-
quency chosen via the CPS control.
High-Frequency Controls (right)
4. KCS: (Kilocycles per second) Sets the operating
frequency of the unit’s high-frequency Boost and
Atten controls.
5. Atten Sel: Sets the operating frequency of the
unit’s high-frequency Atten control.
6. Bandwidth: Sets the width of frequencies affect-
ed by the high-frequency Boost control. Left for
sharp, right for broad.
7. Atten: Sets the amount of attenuation applied to
the frequency set by the Atten Sel control.
8. Boost: Sets the amount of boost applied to the fre-
quency chosen via the KCS control.
9. EQ: Turns the unit on/off. Unit is more fun when
set to “on.”
Note: For proper performance, balanced
TRS must be used for all inputs and outputs.
Important Safety Instructions
the product’s enclosure that may be of
sufcient magnitude to constitute a risk of
electric shock.
The triangular exclamation point icon is
intended to alert the user to the presence
of important operating and maintenance
(servicing) instructions in the literature ac-
companying the product.
The PeQ-501a complies with all applicable
RoHS / WEEE European Union directives.
Do not attempt to service this unit yourself,
as it will void your warranty. Please check
your unit carefully upon receipt and return
to place of purchase immediately if there
are any problems with the product. After
that, the standard Lindell Audio 1 YEAR
warranty will apply to defects in materials
and workmanship.
International Service
For service or warranty assistance, please
contact the Lindell Audio distributor in your
country through the dealer from whom you
purchased this product.
Limited One-Year Warranty
Lindell Audio’s PeQ-501a is warranted by
Lindell Audio to be free from defects in ma-
terials and workmanship for the period of
ONE (1) YEAR to the original purchaser. In
the event of such defects, the product will
be repaired without charge or, at our op-
tion, replaced with a new one if delivered to
Lindell Audio prepaid, together with a copy
of the sales slip or other proof of purchase
date. The warranty excludes problems due
to normal wear, abuse, shipping damage
or failure to use the product in accordance
with the specications.
All parts and labor are covered under this
Limited Warranty. However, if it is deter-
mined by Lindell Audio that the device was
damaged or made defective through abuse,
we reserve the right to charge the customer
for the cost of the repair.
Lindell Audio shall not be liable for damag-
es based upon inconvenience, loss of use
of the product, loss of time, interrupted
operation or commercial loss or any other
damages, whether incidental, consequen-
tial or otherwise. This warranty gives you
specic legal rights, and you may have oth-
er rights, which will vary from state to state.
This warranty is not transferable.
PeQ-501a Features
• Extended high frequency range.: 1K, 1,5K, 2K, 3K,
4K, 5K, 8K, 10K, 12K, 14K, 16K
• Extended low frequency range: 20Hz, 30Hz, 60Hz,
100Hz, 150Hz
• Transformer balanced output
• Designed around vintage 1731 op-amp
• Hand-wound inductor
• All switched rotary controls
• Gold-plated PCB internals
• Real hardware bypass
The infamous low-end trick
Back in 1951, a classic EQ manual instructed users
with this note: “Do not attempt to boost and attenu-
ate simultaneously on the low frequencies.” And of
course, folks did exactly that to see what would hap-
pen.
Due to slight differences in the unit’s the boost and at-
tenuation curves, the result is not that the boost and
attenuation cancel each other out... it just so happens
that this approach can create an EQ curve that can be
very attering to kick drum sounds. Try it; this storied
studio secret is now yours!